Daphni or Dafni (; Katharevousa Δαφνίον, Daphnion) is an 11th-century Byzantine monastery 11 km north-west of central Athens in the suburb of Chaidari, south of Athinon Avenue (GR-8A). It is situated near the forest of the same name, on the Sacred Way that led to Eleusis. The forest covers about 15 to 20 km².